Door frame



Oct 1948. R. R. MAGAW ETAL DOOR FRAME Filed Sept 16, ,1944

3 Sheets-Sheet 1 3 BMagaw Oct. 5, 1948. R. R. MAGAW ETAL 2,450,673

DOOR FRAME Filed Sept. 16, 1944 s Sheets-Sheet 2 I N I 1 a9 S EW' Patented Oct. 5, 1948 UNITED STATES PATENT OFFICE DOOR FRAME Ronald R. Magaw, Canton, and Karl H. Miller,

North Canton, Ohio, assignors to Diebold, Incorporated, Canton, Ohio, a corporation of Ohio Application September 16, 1944, Serial No. 554,442

9 Claims. 1

The invention relates to door frames and more particularly to a knock-down, finishing, sheet metal door frame construction adjustable to varying ceiling heights.

Heretofore, many different types of sheet metal door frames and the like have been made and used. However, there have been numerous difiiculties, disadvantages and objections attendant to their manufacture, shipment and installation.

Thus, some sheet metal door frames have merely provided rough framing elements imbedded in or secured to a plaster or tile wall and additional finishing members of either wood or metal were secured to the rough sheet metal frame after the walls were built.

Also, knock-down finishing sheet metal door frame constructors have been used to some extent, but because of mitering the joints between the head and side jamb members, or for other reasons, it is impossible to provide smooth or uniform or accurate or satisfactory jamb member joints; the frames lack stability, stiffness and rigidity when erected; the frames are subject to twisting or warping of the jam members and loosening of the jamb member corner joints due to the weight of a door hung therein or to repeated opening and closing or slamming of the door; and the frames require the use of bolts, bent tongues and the like for assembly.

There have been satisfactory arrangements of finishing sheet metal door frames provided with adjustable strut members for erection with varying ceiling heights; but no knock-down finishing sheet metal door frame construction with adjustable struts has ever been provided to our knowledge which had sufficient rigidity to satisfactorily install the frames prior to wall completion.

Also, while simple inexpensive adjustable angle strut members have been provided for finishing sheet metal door frames, the ceiling attaching foot of such strut members can only be secured to a ceiling in one or two positions, thereby preventing proper ceiling attachment of the strut members in many cases.

Moreover, most prior sheet metal door frames have included either an inaccessible clip, or a projecting clip, or a clip that must be assembled to the door frame during erection, for providing means for tying metal lath to the door frame in forming a plaster wall around the door frame. These prior door frame lath clips are difficult for workmen to reach, or may become bent requiring straightening. Each of these conditions may cause injury to a workman erecting the door frame; and each condition requires additional unnecessary erection time.

Substantially all prior door frames, whether of wooden or sheet metal construction, except frames for two-way swinging doors and certain types of elevator doors require the door to be located offset from substantially the center plane 'of the door frame and its wall, so that an in-opening door presents a different reveal than an outopening door which may be located nearby in the same room. From an appearance standpoint such .a condition is objectionable in building construction, but no satisfactory way of solving the problem has ever been evolved.

This latter condition has heretofore necessitated a threshold for a door frame, when used, to be located either offset with respect to the center plane of the door or with respect to the center plane of the door frame. When the threshold is located centrally with respect to the center plane of the door it projects beyond one face of the door frame giving an unbalanced appearance.

Also, prior door frame constructions have usually involved hinges and lock strike lips which project from the door frame and may catch on or tear clothing and the like and which also present an undesirable appearance.

It is therefore a fundamental object of the present invention to provide a finishing knockdown sheet metal door frame which overcomes all of the enumerated prior art difficulties, disadvantages and objections.

It is a further object of the present invention to provide a sheet metal door frame which may be installed in a building as a finishing frame around which a plaster or other type of wall may be built.

It is also an object of the present invention to provide a knock-down type of finishing sheet metal door frame which may be manufactured at a factory by simple production methods and operations; readily and easily shipped to a place of installation in knock-down form thus reducing shipping costs; easily assembled and erected in a building by using only a hammer and nails and without requiring special tools; which provides a smooth, uniform and even joint at the corners between the jamb members; which avoids the use of bolts, bent tongues and the like for assembly; and which provides a frame when erected having great stability, rigidity and stiffness against twisting of the frame or loosening of the jamb corner joints or uneven spacing of the faces of the jamb members.

Furthermore, it is an object of the present invention to provide an improved associated clip and cup means of the simplest design which may be readily, easily and cheaply manufactured and permanently assembled to the jamb members, so that the clips hold the sheet metal jamb members rigid. with their. faces properly and unifcrmly spaced; so that the clipsstiifen the head and side jamb members; so that certain clips engage both the head and side jamb members at the corner joints between the head and jamb members; so that the joints between the head" and jamb members may be formed by out sheet metal edges without expensive mitering, grinding and finishing operations so thatthe cups telescope into and interlock between certain clips to rigidly assemble the top jam'b' member to the side jamb members; and so that said assembled cup and clip means provide for the attachment .1, Strut members to the door frame with only the use of a hammer and nails.

It is a further object ofthe present invention to, provide an improved adjustable strut construction for knock-down sheet metal door frames.

Als'o,it is an object of the present invention toprovide an adjustable strut construction for sheetjmetal' door frames utilizing either an angle orflat'bar strut member of simple and cheap dehaving a ceiling, abutting foot which may be nailed or otherwise securedto aceiling in any 10 16. offfourgdifferent positions in order to accomnioda'te every buildingconstructioncondition encountered-in erecting a door frame.

Also, it. is an object of the present invention to providea lath clip means for sheet metal door frameslpenmanently, fabricated as a part of the fiamej'amb members-touniformly space the faces thereofithe clips being accessible but not projectingmaterially from the jamb members thereby. providing forreadily tying metal lath to the door frame without subjecting the workman to possiblewinjuryi Moreover, itisanuobiect of the present invention to. provide: a finishing sheet. metal door frameconstructioninwhich a door may be hung with the same reveal onlboth sides; in which a threshold may be located, if used, within the confinesoftheirame facesand-centrally of the centen-plane of the door. frame and associated .wall; anddnwhichhinges and lock strike members are preferably permanently yfabricated as apart of the side jambmembers without projecting outwardly, therefrom or. from the faces thereof.

Rresent day building constructionusually invol-yes; 2-inch thick plaster walls and when a door frame is erected for providing a door opening invsucir awallformed. therearound; it is desirablelthat the-framefaces should not project morath-an .-a fraction of an inch beyond each wall surface so that. in=many cases the face spacing of; the jambmembers is-not over 2% inches. Other types ofwallgconstruction may. be somewhat thicker but: require a flush door frame. These" conditions have increased the problem :presented b'ecause of the difficulty of overcoming the many other enumerated prior art difiiculties within the confines of such limited space between the jamb membenfaces.

It istheref-ore av further object of the present inventionto provide a sheet metal door frame constructionincorporating, all of the above enumerated characteristics .withinthe confines of an extremely narrow jamb member face spacing.

Finally, it is an object of the present invention to materially and substantially reduce the cost of manufacturing, shipping and erecting finishing sheet metal door frames by providing an improved finishing sheet metal door frame having all of the advantages and characteristics set forth andleliminatingall of the enumerated prior art difficulties';v disadvantages andlobjections.

These and other objects and advantages apparent to those skilled in the art from the following description and claims may be obtained, the stated results achieved, and the described difficulties overcome, by the devices, constructions, arrangements, combinations, sub-combinations,

- parts, and elements which comprise the present invention, the nature of which is set forth in the following general statement, preferred embodiments of whichillustrative of the best modes in which applicants have contemplated applying the princip1esare,set forth in the following descriptionand shown in the drawings, and which are particularly and distinctly pointed out and set forth in the appended claims forming part hereof.

The nature of theimprovements of the present invention may be stated in general terms as pref erably including in knockdown, finishing, sheet metaldoor, frame construction, side andt'op jamb members of channel shape; said members .having die cut abutting edges at the corner joints therelbetween; tubular clips having spaced flat portions permanently connected within the channels to the jamb members atspaced intervals; certain ofsaid tubular clips being-located at the top ends of 'the side jamb members in alignment with other similar, tubular clips at the ends ofthe top jamb member; certain of saidEt-ubular clips permanently-secured to oneofthe frame members projecting beyondthe, channel flange edges thereof and :being telesc-oped between the channel flanges of another jamb member; tubular socket members telescoped within andv interlocked with said aligned clips, other socket members telescoped within. other clips, strut members slidably receivedjn four different positions in rectangular walled apertures insaid socket members; means locking, said strut members with respect t-o-said socket members whereby said clips provide for assemblingtherframemember, for locking the strut members, andfor tying lath to the frame; door hinge and lockstrike means permanently-mounted .on and withinlthe confines of said jamb members; and adoorstop formed in the channel webs ofthe jamb members adjacent one face thereof whereby a door may. be hung, in the door frame presenting-the same-reveal on both-sides of the door frame.

By way of example, preferred embodiments of the improved door frame construction are illustrated in theaocompanying drawings forming part-hereof wherein:

Figure 1 is a front elevation illustrating the improved door frame construction assembled in osition between a-bluilding floor and ceiling;

Fig. 2 is an enlarged fragmentary elevation, with; parts. broken-awayand in section, of an upper cornerof. the improved door frame construction;

Fig; 3 islan enlarged'fragmentary elevation of a lower corner: of therimproved door frame constructionillustrating details of'floor fastening;

Fig. 4aisa=seotionitakenion the line 4-4" of Fig.3;

Fig. 5 isanenlarged section through the hinge side jamb member taken as onthe line 5-5,

Fig. 2;

Fig 6 is an enlarged section through the lock side jamb member taken as on the line 6-6, Fig. 1; i

Fig. 7 is an enlarged detailed corner elevation of the improved door frame construction;

Figs. 8, 9 and 10 are views of the frame assembly cup member illustrated in Fig. 5 with the adjustable strut bar assembled in three other positions;

Fig. 11 is a bracketed perspective view, with the various elements separated, illustrating the improved door frame corner and strut assembly;

Figs. 12 and 13 are top plan views of a modified form of frame and strut assembly cup;

Fig. 14 is a view similar to an upper corner of Fig. 1 illustrating the modified form of strut member shown in Fig. 12; and

Fig. 15 is a view similar to Fig. 7 showing a modified form of mitered corner construction.

Similar numerals refer to similar parts throughout the various figures of the drawings.

Referring to Figs. 1, 2 and 5, the improved door frame is illustrated generally at l and includes a hinge side jamb member 2, a lock side jamb member 3 and a top jamb member 4. Each of the members 2, 3 and 4 have a uniform, substantially channel-shaped cross-section and may be fabricated from a rolled or pressed sheet metal channel. The channel shape in accordance with the present invention presents, in cross-section, a channel flange or frame face portion 5, a channel web or frame opening portion 6 offset at l to form a door stop, a channel flange or frame face portion 8, and inturned flange portions 9 at the outer edges of faces 5 and 8. The corner I ll between portions 5 and 6 and the corner ll between portions 6 and 8 are each rounded.

The hinge side jamb member 2 is cut out at l2 near each end thereof for receiving door hinges 13. The hinges l3 are preferably of special shape with a jamb strap l4 offset in one direction at iii, a door strap l6 offset in the other direction at H, and the strap portions l8 surround the hinge pin I9 and are shaped to conform to the contour of the corner l!) of the hinge side jamb member 2. In fabricating the door frame members, the jamb straps M of the hinges are preferably spot welded at '20 to the inside of frame opening portion 6 so that the hinges I 3 are permanently mounted on the hinge side jamb member 2. Cover plates 2| also preferably are spot welded to the inside of the jamb member 2 to enclose the cut-out portions 12 wherein the hinges l3 are received.

Referring to Figs. 1 and 6, the lock side jamb member 3 is provided intermediate its ends with a lock strike plate 22, permanently secured to the frame opening portion 6 of member 3, and having a lock receiving opening 23 and a strike lip 23a. The door stop offset 1 of the lock side jamb member 3 is also preferably provided with rubber door bumpers 24 generally opposite the hinges b3 mounted in the hinge side jamb '2, as illustrated.

Referring to Figs. '7 and 11, the upper end of each side jamb member 2 and 3 is preferably die cut to provide a straight top edge 25 for flange 9 and face portion 5, a downward miter at 26 adjacent to and around corner [3, a straight edge 2! along frame opening portion 6, a downward notch 28 at door stop offset portion 1, an upward miter 29 around corner H, and a straight edge 30 along frame face portion 8 and its flange 9.

Each end of top jamb member 4 is similarly die cut with a straight edge 3i along face portion 5, a miter 32 around corner [0, a straight edge along frame opening portion 6 and offset 1, a cut back miter 34 around corner H, and a straight edge 35 along frame face portion 8. Thus when the frame members are assembled the die cut edges 25 and 3| abut each other, the cut corner miters 26 and 32 abut each other, the cut corner miters 29 and 34 abut each other, and the out edges 30 and 35 abut each other. The under side of portions 6 and I of the top jamb member 4 overlies the top out edges 21 and 28 of side jamb members 2 and 3, as best shown in Figs. 2 and 11.

The generally horizontal corner jointconstruction illustrated is preferable from an appearance stand point and because the jamb members 2, 3 and 4 can be accurately die cut so that the die cut edges accurately abut each other and form square corners when assembled. If a mitered joint is desired, it may be provided as illustrated in Fig. 15; but the mitered joint may requirea final sawing or grinding operation in order to assure an accurate meeting of the die cut mitered edges and an absolutely square corner.

Clips 36, are preferably bent from a metal strip to form a generally rounded tubular shaped portion 3'! with opposite offset ribs 38 forming spaced flat portions 39. The flats 39 of clips 36 are spot welded at 43 to the inside of the channel jamb members 2 and 3. As illustrated in Fig. 1, these clips 36 are provided at intervals along the side jamb members 2 and 3; and as shown in Fig. 11, the uppermost clip'projects slightly above the top die cut edge of each side jamb member. One or more clips 36 may be welded to the top jamb member intermediate its ends, although none are shown in the drawings. A clip 36 is secured to each end of the top jamb member 4, as illustrated in Fig. 11, and located by spot Welding at 41! so as to be aligned with the top clip 36 in each side jamb member. These clips 36 in being permanently assembled to the jamb members, hold the sheet metal walls of the channel flanges rigid, with their faces 5 and 8 properly and uniformly spaced; and the clips stiffen the head and side jamb members.

In assembling the head and side jamb members, the die cut ends thereof are placed in abutting and interfitting relation, with the uppermost clip 36 at the top of each side jamb member telescolped within and between the face portions 5 and 8 of the top jamb member 4. Cup members 42 are telescoped within the tubular portions 31 of corner clips 36 as best shown in Fig. 2. Each cup or socket member 42 preferably has an end wall 43 and a tubular skirt 44,-split at 45 to provide flexibility and resilience in the skirt portion 44. Outwardly projecting buttons 46 are preferably provided in the socket skirt 44 for engaging in holes 41 formed in each clip 31. so that upon telescoping the socket members 42 within the clips 36 the clips and sockets are interlocked and substantially rigidly held.

Tests upon door frames constructed in accordance with the present invention have shown that the telescoping interlocking connection between the clips and cups, the telescoping of the side jamb member clips between the faces of the ends of the top jamb member, and the rigid spacing of the jamb members by the clips 36, provide a stable and rigid door frame which is very stiff and has strong, smooth corner joints, resistant to twisting or warping of the jamb members and loosening of the jamb corner joints from the ano e-re weight of adoor hung; in thefranie orfrom repeated opening or closingorslamming of the door.-

Moreover, the connection of theframe members-is accomplishedby means-located substantially' entirely within the confines-of the jamb channels, without" the use-of any boltsior bent tongues, and only requiring a hammerto drive the super socket members to assembled positlon. Although clips 36 project slightly beyond flanges 9, the projecting portions are rounded, and the clips are rigidly secured to the lamb member face portions, so that the clips can not be bent easily and are not likely to cause injury toa workman.

A socket member 42a similar to but having a skirt shorter than the'sliift M of the socket member 42 is also assembled within the next to the top clip 36 of eachsidejamb member 2 and 3. Theltop wall as of each socket member 42 and 42a is provided with an opening 48having symmetrical rectangular edges and having recessed notches 49.

In erecting thedoor frame I, after its jamb members have been assembled, a strut bar as formed'ofanglestook is slidably inserted through openings 48 in the spaced cup members 42 and 42a at the top of each: side jambmember 2 and Sand the angled foot 5'! atthe top of each strut bar 50' is nailed or otherwise fastened at 52 to the rough ceiling 53 of the building (Fig. 1). Nails, preferably cut wedge nails 5d are then driven'into one of the socket notches 49 to engageone leg of the strut bar angle and force the other leg against one edge of opening 48, as shown in Figs. 2, 5 and 6.

In Fig. 1', the feet 5| of the strut bars 58' pro ject toward each'other. However, conditions are frequently encountered in building construction 'suchthat the foot 5| of either strut bar 58 may not .be located in the position shown, but must project either forwardly, rearwardly or outwardly, rather than-inwardly of the frame member asishown; However, asillustrated'in Figs; 5, 8, Sand the strut bar 50 may be'inserted into the cup members 12 and 42a in any one of four positions and securely held by the wedge nails 54 because of the symmetrical rectangular edges of openings 48 and the location of notches 49. Thus, the four strutba'r positions shown permitthe foot SI' of any strut bar 511 to extend in any one of four directions along a building ceiling 53. A modified form of cup member #2?) is shown in Figs. 12, 13 and 14 whereina cross-shapedopening' '48a' having substantially symmetrical rec tangular edges is provided with notches Mo and 49b. This cross-shaped opening is adapted to receive a flat bar strut memfber 58min anyone of four positions; two positions being illustrated in Figs. 12 andle and two positions being illustrated in Fig. 13. The strut bar 5011 is likewise secured'to the cup member 421) by a nail 54.

A flanged clip member 55 is' spot welded at 59 to the bottom ends of each sidexjamb member 2 and -3 for fastening the lower ends of the side J'amb members by nailing at 5! to the usual grooved Wooden floor strip 58.

After the door frame 1 has been erected, pant'ition lath channels may :be erected in' accord anoe with usual practice, preferably'spaced some distance from each side frame member as indi cate'd'at 59 in Figs. '5 and 6; Metal lath -61] *issecured to the lath channels 59 an'd may 'be tied to the clips 35 andto the holes 6i provided in' strut members 50. A plaster wall 62 is then formed on the metal'lath with the plaster'running inward in locking engagement with the frame flanges 9, as indicated at 63. If desired, the plasterwall may be thicker so that its surfaces are flush with the outer face surfaces of the lamb member face portions 5 and 8.

If the improved door frame is to be erected in a. tile or terra cotta wall, which may be somewhat thicker than the plaster wall illustrated, a door frame having a wider space between face portions5'and 3 may be used.

Referring to Figs. 2 and 5, a door 64 may be hung in the door frame I by screws 65 secured throughhingestrap 16 to the door 64. The door 64 will open to a position shown in dot-dash lines in Fig. 5, completely clearing the door frame. When closed, the center plane of the door 64 is located in the-center plane of the door frame I because of the location of the door stop 'l'closely adjacent the channel face portion 8. Thus, the same reveal is presented at either side of the door. Likewise, if a threshold is provided for the door frame I, the outer edges of which are indicated at 66 in Figs. 5 and 6, the threshold is located centrally of the door and the door frame, and Within the space between the frame face portions 5 and 8, so as to present a balanced appearance.

By hanging the door centrally of the door frame so as to present the same reveal on each side, it is possible to move the lip 23a of the lock strike plate 23 inward so that it does not project beyond the face 5 of the door frame, as shown in Fig. 6. The rounding of the corner it conforms to the rounding to of the hinges so that the door frame with the door closed presents a uniform appearance on the hinge side. The insetting of the hinges and of the lip of the lock strike plate removes an objectionable projection of these members present in usual building construction.

The door frame I may be completely fabricated in a shop and shipped in knock-down form to the place of erection occupying little space during shipment. When erected it provides a finishing door frame without requiring any finishing molding or door stop strips to be applied thereto. The adjustable strut members adapt to door frames to varying building conditions.

Accordingly, the improved door frame construction provides a finishing sheet metal door frame of knock-down construction with smooth, uniform, rigid and stable corner joints and jamb members when erected; with adjustable struts which may be erected to meet various building conditions encountered; with permanently attached frame member spacing clips for assembling the jamb members, attaching the strut members, and for attaching wall lath; in which a'door may be hung, without projecting hinges and lock strikes, centrally of the frame to present the same reveal on both sides of the door; and all of which advantages are taken care of in a satisfactory manner in a frame having a minimum width.

The embodiments of the present improvements are illustrated and described herein by way of example, and the scope of the present invention is not limited to the exact details of construction of the various parts.

Finally, in the foregoing description certain terms have been used for brevity, clearness and understanding; but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such words are utilized "for descriptive purposes herein and not for the purpose of limitation, and are intended to be broadly construed.

Having now described the features of the invention, the construction, erection and use of preferred embodiments thereof, and the advantageous, new and useful results obtained by the improved constructions; the new and useful devices, constructions, arrangements, combinations, sub-combinations, parts and elements, and reasonable mechanical equivalents thereof obvious to those skilled in the art, are set forth in the appended claims.

We claim:

1. In a knock-down, sheet metal door frame having side and top jamb members of channel shape, a connection construction for the corner joint abutting edges of the members including, tubular clip means at the top of each side jamb member, tubular clip means at each end of the top jamb member, said tubular clip means each having spaced flat portions permanently secured to the jamb member channel flanges within the channel, the clip means at each corner joint being tubularly aligned, and a tubular socket member telescoped within and interlocked with said aligned clip means.

2. In a knock-down, sheet metal door frame having side and top jamb members of channel shape, a connection construction for the corner joint abutting edges of the members including, tubular clip means at the top end of each side J'amb member, tubular-clip means at each end of the top jamb member, said tubular clip means each having spaced flat portions permanently secured to the jamb member channel flanges within the channel, the clip means at each corner joint being tubularly aligned, a tubular socket member telescoped within said aligned clip means and connecting the corner joints, the tubular clip means on one of the frame members at each corner joint projecting beyond the channel flange edges thereof and being telescoped between the channel flanges of the other jamb member.

3. In a knock-down, sheet metal door frame having side and top jamb members of channel shape, a connection construction for the corner joint between the top and a side jamb member including, interfltting die cut formations at the ends of said top and side jamb members with the die cut channel flanges in edge abutment forming smooth frame face joints, a tubular clip at the top end of the side jamb member, a tubular clip at an end of the top jamb member aligned with said side jamb member clip, said tubular clips each having spaced flat portions permanently secured to the jamb member channel flanges within the channel, and a tubular socket member telescoped within and secured to said aligned clips to form a rigid corner joint.

4. In a knock-down, sheet metal door frame having side and top jamb members of channel shape, tubular clips having spaced flat portions permanently secured to the jamb member channel flanges at spaced intervals within the channel, certain of said clips being located at the top ends of the side jamb members in alignment with other similar clips at the ends of the top jamb member, and tubular socket members telescoped within and secured to each of said aligned clips.

5. In a knock-down, sheet metal door frame having side and top jamb members of channel shape, tubular clips having spaced flat portions permanently secured to the jamb member channel flanges at spaced intervals within the channel, certain of said clips being located at the top ends of the side jamb members in alignment with other similar clips at the ends of the top jamb member, certain of said clips at the corner joints between the jamb members projecting beyond the channel flange edges of one of the jamb members and being telescoped between the channel flanges of the other jamb member, and tubular socket members telescoped within and secured to each of said aligned clips.

6. A corner construction for the abutting corner edges of channel shaped side and top sheet metal door frame jamb members, a tubular clip having flat faces secured within the top member between the channel flanges at the end thereof, a similar tubular clip secured within the side member between the channel flanges at the end thereof, the clip on one of the jamb members projecting between the channel flanges of the other jamb member, said clips rigidly spacing and stiffening the flanges of the jamb members against deflection and twisting, and means telescoped within the tubular clips connecting the frame members.

'7. In a knock-down, sheet metal door frame, side and top jamb members of channel shape, interlocking tubular means connected to and forming the corner joint between the side and top jamb members, said corner joint connecting means having a wall formed with a rectangularly shaped aperture, a strut member slidably received in four diflerent positions in said aperture, and means locking said strut member to said connecting means.

8. In a knock-down, sheet metal door frame, side and top jamb members of channel shape tubular corner joint connecting means between the side and top jamb members, a substantially symmetrical rectangularly walled aperture formed in said connecting means, astrut bar slidably received in four different positions in said aperture, and means locking said strut bar to said connecting means.

9. In a knock-down, sheet metal door frame, side and top jamb members of channel shape, tubular corner joint connecting means for said members, a substantially square aperture formed in said connecting means, a strut bar slidably received in four different positions in said aperture, and means locking said strut bar to said connecting means.

RONALD R. MAGAW. KARL H. MILLER.

REFERENCES CITED.

The following references are of record in the flle of this patent:

UNITED STATES PATENTS Number Name Date 936,451 Havenhill Oct. 12, 1909 1,723,281 Levy Aug. 6, 1929 1,761,288 Baum June 3, 1930 1,919,071 Mills July 18, 1933 2,284,012 Paca. May 26, 1942 2,316,829 Zecca Apr. 20, 1943 

